Many of the ideas are taken from XMonad which is also used by people who like it and at the same time is also an excellent example of how monadic window management works. LISP is like that, everything in LISP is just a DSL so it is scriptable.
You are right before that Linux is becoming professional. It has been far too successful in too many areas to want to keep the hacker culture that existed 20 years ago. Of course the BSDs still have that. But you like hacker OSes go with something much more interesting than a UNIX. House / HaLVM (also Haskell) are pretty cool extensions for the modern world.
As far as tiling window managers for Wayland they already exist and I'd assume will get more sophisticated with time: There is Velox which is a varient of XMonad and Orbment:
https://www.youtube.com/watch?...
It seems like as things currently stand most of the pieces to do this exist. X does remote display. PulseAudio does network audio (though I am struggling to make that work). There is USB over TCP/IP support in Linux but you have to go to the commandline and tell a client to share a specific USB device
Wayland does Audio and Video now and can keep them unified. usb device redirection is part of the protocol so GTK/Qt should be implementing controllers that work within their respective desktops.
Anyway, implementing all of this.. if remote support is fragmented across toolkits, possibly non-existent on some lesser used toolkits.. that sounds even harder than it has ever been!
No it is far far easier. GTK, Qt, wxWindows, Mono... all understand that USB and sound exist so no hacking. For example Gnome -> Gnome can pass off intelligent information about streaming and buffering so remote sound is both good and responsive even if the lots of jitter on the network. USB of course requires device driver virtualization and the toolkits, already support that. Etc... This all becomes almost trivial.
Once you start trying to use Wayland the way it is meant to be used this becomes easy.
I think there would be a lot to gain if thin-clients were to become more mainstream.
They are mainstream its called remote desktop. That is in 2015 people using thing clients aren't remoting the video but remoting the desktop. The reason is that is doesn't cost much to add some CPU and video to the local machine and it makes it much more responsive. So the local system has a thin base OS. It loads toolkit information from a server when it isn't being used. When it is being used the server just passes it specifics about what's running. This is the model that can go on top of RDP which is what Wayland is implementing.
Wayland doesn't make thin client less practical but rather makes it vastly more practical because you'll be able to thin the client down to something like an Android device and thus have the base OS built in. Microsoft is way ahead of Linux on thin client, because of how naive is about toolkits.